Carbamylalkenyl phosphoruscontaining esters



United States ,PatentO CARBAMYLALKENYL PHOSPHORUS- CONTAINING ESTERS 6 Claims. (Cl. 260-461) This invention relates to a new class of phosphoruscontaining esters which have been found 'to be particularly useful as insecticides.

The compounds of the invention are carbamylalkenyl phosphorus-containing esters of the formula:

wherein X is a member of the class of radicals consisting of RO, RNH- and RzN- in which R is an alkyl group containing up to 6 carbon atoms; R is a monovalent hydrocarbon radical; each R" is a member of the class consisting of a hydrogen atom and an alkyl radical; each R' taken singly is a member of the class consisting of a hydrogen atom, a monovalent hydrocarbon radical, a nitroaryl radical, a haloaryl radical, an alkoxyaryl radical, a cyanoaryl radical, an acyloxyaryl radical, and taken together in combination, a divalent hydrocarbon radical with 4 to saturated carbon atoms in a chain between the two valences; m is an integer of 1 to 2; and n'=3m. Thus, for example, R is any alkyl radical of up to 6 carbon atoms such as methyl, ethyl, isopropyl, butyl, isopentyl, hexyl or B-hexyl. R is any monovalent hydrocarbon radical such as methyl, ethyl, isobutyl, 3-hexyl, decyl, octadecyl, allyl, crotyl, oleyl, propargyl, phenyl, xylyl, diphenyl, naphthyl, cyclopentyl, cyclop'e'ntenyl, cycohexyl or isopropylcyclohexyl. Each R" is the same or different and is a hydrogen atom or a methyl, ethyl, isobutyl, hexyl, 2-oetyl, dodecyl, hexadecyl or any other alkyl radical. Taken singly, each R is the same or different and is a hydrogen atom or any monovalent hydrocarbon radical such as was exemplified for R; or is a nitroaryl radical such as a p-nitrophenyl radical, an onitrophenyl radical, a nitrotolyl radical, a nitronaphthyl radical, etc.; or is a haloaryl radical such as a chlorophenyl radical, a bromophenyl radical, an iodotolyl radical, etc.; or is an alkoxyaryl radical such as a methoxyphenyl radical, a butoxytolyl radical, etc.; or is a cyanoaryl radical such as a cyanophenyl radical, a cyanonaphthyl radical, etc.; or is an acyloxyaryl radical such as an acetoxyphenyl radical, a butyroxyphenyl radical, etc. Taken together, the R"s are a divalent hydrocarbon radical with 4 to 5 saturated carbon atoms in a chain between the two valences such as a tetramethylene radical, as in a pyrrolidyl group, or a pentamethylene radical, as in a piperidyl group, and homologues thereof. It will be noted from the above formula that when m is 'the integer '1, n+l=1 and the compound is a phosphonate; and that when m is the integer 2, n-1=0 and the compound is a related phosphate. Preferably, the compounds have alkyl groups as the hydrocarbon radicals, and it is further preferred that the compounds be derivatives of N,N-dialkyl alphachloroacetoacetamide.

The new compounds of the invention are prepared by reacting an appropriate phosphonite or phosphite with a'lph'a-chloro beta-0x0 fatty acid amide. Thus, when'a 2,802,855 Patented Au 13, 1957 dialkyl hydrocarbon-ph'osphonite is used, the reaction involved may be written as follows:

Similarly, when a trialkyl phosphite is used, the reaction involved may be written as follows:

In like manner whenan alkyl N,N,N,N-tetraalkylphosphorodiamidite is used, the reaction involved may also be written as follows:

In these equations, the several-Rs represent the same kind of atoms or radicals as noted above for the 'firstmentioned formula.

The reactions are'eifected by adding about an equimolar amount of the chloroester to the phosphonite or phosphite,

the addition usually being made slowly so as to avoid undue temperature increase of the reaction mixture from the exothermic heat of reaction. The reaction may be started with the reactants at an ordinary temperature of about 20 C. to 25 C., but for the most part is conducted preferably at a temperature between about 60 C. and C. In some cases, the starting of the reaction is'assisted by application of heat, and especially if large quantities of reactants are used, cooling is employed to control the temperature within the desired range. The formed alkyl chloride is preferably "removed from the reaction mixture to greater or lesser extent byap licatien of sufficient vacuum so the chlorideis boiled out. When the boiling points of the formed alkyl chloride and the chloroester reactant are fairly close together, use of a distillation column for removal of the alkyl chloride is advisable for best results. Some of the higher reactants are solids at ordinary temperature, but use of an inert solvent such as Xylene enables a fluid reaction system to be realized. Use of a solventis not essential, however. The react-ion is effected under substantially anhydrous conditions. in order to insure completion of the reaction after addition of the chloroester, the reaction mixture is heated within the indicated temperature range for a reasonable time. The formed phosphonate or phosphate product is usually recovered by distillation under sufficiently low pressure that thermal decomposition is avoided. If desired, especially with higher compounds of the invention, crystallization of molecular distillation may be used for recovery of the desired product. p

Although it is preferred to prepare the compounds from an alphachloro beta-0x0 fatty acid amide in the manner described above, they may alsobe prepared from'a'n alphabromo beta-0x0 fatty acid amide by substitution of the bromo compound in place of the chloro'conipound.

the class of new compounds of the invention are described in detail in the following examples wherein the parts are by weight.

Example I Diethyl l-dimethylcarbamyl-l-propen-Z-yl phosphate was prepared by reacting triethyl phosphite with alphaehloro-N,N-dimethylacetoacetamide, which last-named compound was obtained by first reacting diketene with dimethylamine and then reacting the resulting N,N-dimethyl aeetoacetamide with sulfuryl chloride in the following manner:

Diketene in amount of 126 parts (1.5 mols) was added drop-wise during a period of about an hour to a stirred solution of 68 parts of dimethylamine in 800 parts of water while maintaining the temperature of the reaction mixture at C. to C. The mixture was then stirred for an additional hour, after which the aqueous solution was evaporated to a residue of 180 parts which was distilled. The desired N,N-dimethyl acetoacetamide in amount of 142 parts distilled at 80-83 C. at 0.5 mm. pressure.

Sulfuryl chloride in amount of 143.5 parts (1.07 mols) was added drop-wise to 138 parts (1.07 mols) of N,N

dimethyl acetoacetamide held at about 10 C., after which the mixture was warmed to C. to remove the majority of the hydrogen chloride. The residue was then distilled and 156 parts of alpha-chloro-N,N-dimethylacetoacetamide was recovered which distilled at 93-98 C. at 0.5 mm. pressure. The liquid amide was found to contain 22.0% chlorine (theory: 21.7%).

Triethyl phosphite in amount of 158.5 parts (0.954 mol) was added drop-wise to 156 parts (0.954 mol) of alpha-chloro-N,N dimethyl acetoacetamide while maintaining the reaction mixture at -l10 C. After the addition, the mixture was evacuated and it was found that 50 parts of material had collected in a cold trap, the theoretical amount of ethyl chloride formed would be 61.5 parts. The residue of the reaction mixture in amount of 254 parts was distilled and 145 parts of the desired diethyl l-dimethylcarbamyl-l-propen-2-yl phosphate was collected. The phosphate was a liquid which undergoes molecular distillation at 132 C. under 1 l0 mm. pressure and has a refractive index (ZO/D) of 1.4663. Analysis showed the ester contained 11.8% phosphorus (theory: 11.7%) and 4.9% nitrogen (theory: 5.3%). The ester was found to be soluble in water, in isopropyl alcohol, in acetone, and in benzene.

Example II Diethyl l-phenylcarbamyl-1-propen-2-yl phosphate of the formula 0 CH: O

was prepared by adding 71 parts (0.426 mol) of triethyl phosphite dropwise with stirring to parts (0.426 mol) of alpha-chloro-acetoacetanilide. The reaction caused the mixture to warm a little. After the addition was completed, the reaction mixture was heated to -110" C. and 14.5 parts of material was recovered in a cold trap cooled with an acetone-solid carbon dioxide bath upon evacuating the reaction mixture at av pressure of about 200 mm. The reaction mixture was permitted to cool to room temperature whereupon some crystallization occurred. The mixture was filtered and 12 parts of alphachloroacetoacetanilide were recovered. The filtrate was then subjected to molecular distillation and about 20 parts of material largely comprising alpha-chloroacetoacentanilide were recovered. The residue was dissolved in hot ethanol, and water was added to incipient cloudiness. On cooling, the product crystallized and was removed by filtration. This purification operation was repeated twice again, and the desired diethyl l-phenylcarbamyl-l-propen-Z-yl phosphate was recovered as a crystalline solid melting at 81-81.5 C. The phosphate was soluble in benzene, in isopropyl alcohol, and in acetone, but was insoluble in water. Analysis of the ester gave the following results:

Example III Diethyl 1-(p-nitrophenylcarbamyl)-l-propen-Z-yl phosphate of the formula was prepared by reaction of triethyl phosphite with alphachloro-p-nitroacetoacetanilide. The latter was prepared by reaction of p-nitro-aniline with ethyl acetoacetate and then treating the resultant p-nitro-acetoacetanilide with sulfuryl chloride.

Triethyl phosphite in amount of 32.3 parts (0.195 mol) was added slowly with stirring to 50 parts (0.195 mol) of alpha-chlorop-nitroacetoacetanilide. The reaction was exothermic and the temperature was maintained between about 80 and C. by the rate of addition. An additional 10 parts of triethyl phosphite was added and the mixture heated at 120 C. for 30 minutes to insure complete reaction, the excess triethyl phosphite being removed later by distillation at low pressure. By-product ethyl chloride in amount of 11.7 parts (0.181 mol) was collected'in a cold trap. The crude product was dissolved in hot ethanoland the solution decolorized with charcoal. Water was added to the clear hot filtrate from the charcoal treatment until incipient cloudiness occurred, after which the mixture wasallowed to cool slowly. The crystalline product in amount of 34.2 parts was then re crystallized as above to give 30 parts (43% of theory) of diethyl l-(p-nitrophenylcarbamyl)-l-propen-2-yl phosphate which was a crystalline solid having a melting point of l43l44 C. Analysis of the ester gave the following results:

Example IV Diethyl l-(methylphenylcarbamyl)-1-propen-2-y1 phosphate of the formula.

0 OHa 0 CH3 was prepared by reaction of triethyl phosphite and alphachloro-N-methylacetoacetanilide. Some 214 parts (2.0 mols) of N-methylaniline and 260 parts (2.0 mols) of ethyl acetoacetate were first mixed and heated for one hour in an open vessel. During this period, the temperature rose to about 200 C. The crude product was then cooled and reacted with about 1360 parts of 2 N sodium hydroxide solution. The crude insoluble sodium salt was collected by filtration, air dried to remove water and thoroughly washed with Skellysolve A (pentanes) to give 224 parts (53% of theory) of the sodium derivative of N-methylacetoacetanilide which analyzed as containing 10.7% sodium (10.8% calculated) and 6.3% nitrogen (6.6% calculated). Some 170 parts (0.9 mol) of N-methylacetoacetanilide was obtained in a crude state by dissolving 224 parts (1.05 mols) of the sodium derivative in a minimum amount of water, acidifying with dilute acetic acid, extracting with chloroform and distilling oil? the solvent. The N-methylacetoacetanilide was dissolved in about 375 parts of chloroform andvslowly reacted with 146 parts (1.08 mols) of sulfuryl chloride. The temperature was maintained at about C. during the reaction and afterwards raised to reflux temperature for 2.5 hours. The solvent was removed by distilling until the kettle contents reached 110 C. at 0.5 mm. pressure. About 133.5 parts (66% of theory) of alphachloro-N-methylacetoacetanilide was obtained by twice distilling the residue in a falling-film molecular still at 95100 C. and 0,0005 mm. pressure. The product was a viscous liquid having a refractive index (19/D) of 1.5472. It analyzed as containing 20.7% chlorine (15.8% calculated) and 5.7% nitrogen (6.2% calculated). v p

Triethyl phosphite in amount of 41.5 parts (0.25 mol) was added slowly to 56.4 parts (0.25 mol) of alphachloro-N-methyl-acetoacetanilide. increased about 95 C. to initiate the reaction and then was maintained at about 65 C. for 3 hours to complete the reaction. By-product ethyl chloride in amount of 12.3 parts (0.191 mol) was collected in a cold trap while heating the crude product at 65-95 C. under vacuum. Diet-hyl l-(methylphenylcarbamyl) 1-propen-2-yl phosphate was obtained in amount of 58.4 parts (71.5% of theory) by twice distilling this crude product in a fallingfilm molecular still at 115-120 C. and 0.001 mm. pressure. The product was a viscous oil having a refractive index (20/D) of 1.5164. Analysis of the ester gave the following results:

Found Calculated Percent carbon 54. 6 55. 1 Percent hydrogem. 6. 7 6. 7 Percent nitrogen. 4. 3 4. 3 Percent phosphorus 10. 0 9. 5

Other compounds of the invention are prepared in similar fashion. For example, methyl l-carba'myl-lr propen-2yl methylphosphonate is obtained by reacting alpha-chloroacetoacetamide with dirnethyl methylphosphonite; ethyl l-ethylcarbamyl-1-propen-2 yl butylphosphonate is obtained by reacting alpha-chloro-N-ethylacetoacetamide with diethyl butylphosphonite; ethyl lcarbamyl-1-ethen-2-yl phenylphosphonat'e is obtained by reacting alpha-chloroformylacetanilide with diethyl phenylphosphonite; butyl 2 diphenylcarbamyl S-methyllbuten-l-yl cyclohexylphosphonate is obtained by reacting alpha chloro N,N diphenyl alpha formylisovaleramide with dibutyl cyclohexylphosphonite; ethyl l-allylcarbamyl-l-propen-2 yl allylphosphonate is obtained by reacting alpha-chloro-N-allylacetoacetamide with diethyl The temperature was formylacetamide with trihexyl phosphite; dibutyl 2-diphenylcarbamyl fi-met-hyl-l-buten-l-yl phosphate is obtained by ,reacting alpha chloro-N,N-diphenyl alphaforrnylisolvaleramide with tributyl phosphite; diethyl 1- allylcarbamyl-l propen-2-yl phosphate is obtained by reacting alphabhloro-N-allylacetoacetamide with triethyl phosphite; I dimethyl 2-cyclohexylcarbamyl-2-buten-3@yl phosphate is obtained by reacting alpha-chloro-N-cyclohexyl-alphaeacetopropionamide with trimethyl phosphite; diisopropyl l-dimethylcarbarnyl-1-propen-2-yl phosphate is obtained by reatcing alpha chloro-NN-dimethylacetoacetamide with triisopropyl phosphite; diethyl 3-ethylcarbamyl-2-tridecen-2eyl phosphate is obtained by reacting alpha-chloro-N-ethyl alpha-acetolauramide with 1 triethyl phosphite; dimethyl 7 l-phenyl carbamyl-l-propen-2-yl phosphate is obtained by reacting alpha-chloro-acetoacetanilide with trimethyl phosphite; diethyl l-(rn-nitrophenylcarbamyl)-1-propen-2-yl phosphate is obtained by reacting alpha-chloro-m-nitro-acetoacetanilide with triethyl phosphite; dimethyl 1-(o-methoxyphenyhcarbamyl)'-1- propen-2-yl phosphate is obtained by reacting alpha-chloro-o methoxyacetoacetanilide with trimethyl phosphite; butyl 1-(p=bromophenylcarbamyl) l-propen-2 yl methylphosphonate is obtained by reacting alpha-chloro-p'-bromoacetoacetanilide with dibutyl methylphosphonite; N, N,N',N-tetraethyl l-carbamyl-l-propen-Z yl phosphorodiamidate is obtained by'reacting alpha-chloroacetoacetamide with ethyl N,N,N,N'-tetraethylphosphorodiamidite; N-,N' dibutyl 1 dimethylcarbamyl 1 propene 2- yl phosphorodiamidate is obtained by reacting ethyl N,- N'-dibutylphosphoro diamidite with N,N-dimethyl 2- chloro-acetoa'cetamide; and N,N-diethyl l-pentamethylenecarbamyl-1-propen-2-yl ethylphosphonamidate is obtained by reacting alpha-chloroacetoacetylpiperidide with ethyl N,N-diethylethyl-phosphonamidite. The chloroamide reactants can be prepared by reacting a beta-0x0 fatty acid amide: with sulfuryl chloride according to the method described in Ann., vol. 439, page 211 (1924). The beta-0x0 fatty acid amides are obtainable by the methods described in U. S. Patents 2,145,617; 2,152,132; 2,323,938 and 2,561,205. The phosphite and phosphonite reactants are readily obtainable by known methods referred to in the book by G. M. Kosolapoff, Organophosphorus Compounds (1950).

Many of the complex arylphosphonates of the invention are liquids at ordinary temperatures of 20 C. to 25 although higher members are crystalline solids at such normal temperatures. The new compounds are very useful substances for a variety of applications such as additives for lubricating oils and greases, as platicize'rs for vinyl resins. and the like, and as raw materials of intermediates for synthesis of a variety of chemical products. The compounds have particular utility as insecticides because they possess outstanding properties when employed as contact insecticides. The compounds are highly toxic to i'nsects, a term which is employed herein to include not only the members of the class Insecta, but also related or similar non-vertebrate animal organisms belonging to the allied classes of arthropods and includingmites, ticks, spiders, wood lice, and the like.

The compounds of this invention can be employed for insecticidal purposes by the use of any of the methods which are conventionally employed in that art. For example, the compounds can'either be sprayed or otherwise applied in the form of a solution or dispersion, or they can be absorbedon an inert, finely divided solid and applied as a dust. Useful solutions for application by spraying, brushing, dipping, and the like, can be prepared by using as the solvent any of the well-known inert horticultural carriers, including neutral hydrocarbons such as kerosene and other light mineral oil distillates of intermediate viscosity and volatility. Adjuvants, such as spreading or wetting agents, can also be included in the solutions, representative materials of this character being fatty acid soaps, rosin salts, saponins, gelatin, casein, long a chain fatty alcohols, alkyl aryl sulfonates, long-chain alkyl 'sulfonates, phenolethylene oxide condensates, C12 to C20 persing the same into the atmosphere by means of a compressed gas.

Many of the compounds can also be used as systemic poisons. In this case the compounds, either with or without a suitable carrier or diluent, can be applied to the soil in the vicinity of the growing plant to be protected (with the compound then being absorbed from the soil by'the plant) or they can be applied directly to the plant where they are again distributed throughout the plant tissues. In either case the plant as a whole then becomes toxic to insects which consume any portion thereof.

The concentration of the compoundsto be used with the above carriers is dependent upon many factors, including the particular compound utilized, the carrier employed, the method and conditions of application, and the insect species to be controlled, a proper consideration and resolution of these factors being within the skill of those versed in the insecticide art. In general, however, the compounds of this invention are effective in concentrations of from about 0.01 to 2% based upon the total weight of the composition, though under some circumstances as little as about 0.001% or as much as 5% or even more of the compound can be employed with good resultsfrom' an insecticidal standpoint.

When employed as an insecticide, a compound of this invention can be employed either as the sole toxic ingredient of the insecticidal composition or it can be employed in conjunction with other insecticidally-active materials. Representative insecticides of this latter class include the naturally-occurring insecticides such as pyrethrum, rotenone, sabadilla, and the like, as well as the various synthetic insecticides, including DDT, benzene hexachloride, thiodiphenylamine, cyanides, tetraethyl pyrophosphate, parathion, azobenzene,'and the various compounds of arsenic, lead, and/or fluorine.

In the following examples, the insecticidal qualities of two typical compounds of the invention described in Examples I and II, are demonstrated.

Example V Toxic agent: LD-50 Diethyl l-dimethylcarbamyl-lpropen-Z-yl phosphate 0.02 Diethyl l-phenylcarbamyl-lpropen-Z-yl phosphate 0.15

Example VI The residual toxicity of two compounds of the invention described in Examples Iand II were determined. Emulsible concentrates were prepared containing by volume: 25% toxicant, 65% xylene, 5% Triton X 155 emulsifier, and 5% Triton 13-1956. Portions of, the concentrates were mixed and shaken with water in such proportions as to give the concentrations tabulated below. The. aqueous emulsions were sprayed in uniform fashion on'the underside of two primary leaves of potted Pinto bean plants. This was accomplished by fastening the tips of the two leaves in a vertical position with the upper surfaces touching each other and rotating the plants on a turntable while applying the spray. One day after the spray applications were made, the plants were infested with 2-spotted mites, Tetranychus bimaculatus. A mortality count of the mites was then made 24 hours later with the following results:

Toxic Agent Cone. Wt. Percent Percent Mortality Diethyl 1-dimethylcarbamyl-1-propen-2-yl l. 25 94 phosph e 0. 25 13 Diethyl 1 phenylcarbamyl 1 ropen 2 yl 1. 25 98 phosphate 0. 25 25 We claim as our invention:

1. A compound represented by the formula:

RI! RI! 0 RI! Xm-i OC I=(iI-( iN u/ wherein X is a member of the'class of radicals consisting of RO, RNH and RzN-- in which R is an alkyl group containing up to 6 carbon atoms; R is a member of the class consisting of an allyl, crotyl, oleyl, propargyl, phenyl, xylyl, diphenyl, naphthyl, cyclopentyl, cyclopentenyl, cyclohexyl, isopropylycyclohexyl, and alkyl radicals of up to 18 carbon atoms; each R" is a member of the class consisting of a hydrogen atom and an alkyl radical of up to 16 carbon atoms; each R' is a member of the class consisting of a hydrogen atom, an allyl radical, a crotyl radical, an oleyl radical, a propargyl radical, a phenyl radical, a Xylyl radical, a diphenyl radical, a naphthyl radical, a cyclopentyl radical, a cyclopentenyl radical, a cyclohexyl radical, an isopropylcyclohexyl radical, an alkyl radical of up to 18 carbon atoms, a mononitroaryl radical of 6 to 10 carbon atoms, a halophenyl radical, an alkoxyphenyl radical containing up to 4 carbon atoms in alkoxy group, an alkoxytolyl radical containing up to 4 carbon atoms in the alkoxy group, and an acyloxyphenyl radical with the acyloxygroup thereof being saturated and containing 2 to 4 carbon atoms; in is an integer of 1 to 2; and n=3m. i

2. Ethyl 1-carbamyl-l-ethen-2-yl phenylphosphonate.

3. Diethyl 1-dimethylcarbamyhl-propen-Z-yl phosphate.

4. Diethyl l-phenylcarbamyl-l-propen-2-yl phosphate.

5. Diethyl 1 (p nitrophenylcarbamyl)-1-propen-2-yl phosphate. 7 V

6. Diethyl l (methylphenylcarbamyl)-l-propen-2-yl phosphate. p

References Cited in the file of this patent UNITED STATES PATENTS 2,494,283 Cassaday et al Jan. 10, 1950 

1. A COMPOUND REPRESENTED BY THE FORMULA: 